find_mac.rb

require "rubygems"
require "snmp"

mac = ARGV.shift.dup
unless mac.gsub! /^(..)[-: ]?(..)[-: ]?(..)[-: ]?(..)[-: ]?(..)[-: ]?(..)[-: ]?$/, '\1 \2 \3 \4 \5 \6'
  puts "illegal mac"
  exit
end

mac = mac.split(" ").collect { |hex| eval("0x#{hex}").to_s }.join "."


%w[240 113 175 184 185 179 241 193 194 176 177 178 202].each do |ip|
  SNMP::Manager.open(:Host => "192.168.1.#{ip}") do |snmp|
    value = snmp.get_value("SNMPv2-SMI::mib-2.17.4.3.1.2.#{mac}")
    puts "192.168.1.#{ip}, port #{value}" unless value.to_s =~ /noSuchInstance/
  end
end